Tag: rock salt

Salt or sodium?

The only thing that differentiates table salt, sea salt, rock salt, Himalayan rock salt or organic salt is a few minerals and a marketing strategy – they are the same thing. Salt or sodium chloride is the primary source of sodium for the human body.

Sodium Chloride has two elements –
sodium (40%) and chloride (60%)

Sodium is a key component of our body for regulating fluids i.e. our blood volume. Too much sodium increases the volume of the blood (by attracting water) thereby adding stress to the blood vessels and heart (more blood to pump around) and resulting in increased blood pressure. The connection between high blood pressure and increased risk of strokes, cardiovascular disease has been firmly established (1).

What is the evidence?

Initially, it was the Intersalt observational study (2) which found the association between sodium and blood pressure. Since then many randomised controlled trials have been organised to test this association.
Evidence of sodium intake affecting blood pressure is definite. The World Health Organisation (WHO) conducted a meta-analysisandsystematic review. The overall objective was to assess the effect of reduced sodium intake on blood pressure, kidney function and blood lipids. Other specific objectives include looking at the effect of consuming less salt compared with consuming more and reducing the salt by varying amounts to establish the best intake zone (3).

A reduction in salt intake is able to reduce resting diastolic blood pressure.

For the greatest positive effect in systolic and diastolic pressure, the sodium intake was less than 2g (5g salt) per day,

The same meta-analysis also confirmed blood lipids (total cholesterol, HDL and LDL and triglycerides) were not affected by changes in salt (3).

The evidence for reducing salt in the diet for healthy blood pressure and the evidence for raised blood pressure being a significant factor in strokes and cardiovascular disease is of highquality.

Population Health

The relationship between high salt intake and increased systolic blood pressure (and thereby cardiovascular disease) makes high salt intake a major population health concern. WHO considers reducing daily salt intake will have significant health and financial benefits to the global population. New Zealand modelling has found similar effects and NZ would benefit financially and in terms of life quality with population salt reduction.

1 gram of sodium chloride (salt) contains 390 mg sodium

WHO stronglyrecommends the intake of sodium be less than 2g/day (5g of salt). This equates to a global target of a 30% sodium reduction with a targeted date of 2025 (4).

Current daily salt intake around the world is shown in the graph below – Australia 9.6g (5), New Zealand 8.4g (6), United States 8.3g (7) and United Kingdom 8.0g (8).

The daily salt intakes in Australia, New Zealand, United Kingdom and the United States is well above the WHO recommendation of 5g/day

Global initiatives

The majority of sodium comes from processed foods and it is challenging to leave the salt out of food processing. Changing the salt content in the food affects many things – taste, texture, shelf life and food safety. Initiatives to reformulate food with this goal in mind has been undertaken globally. Incognito salt reductions have already been accepted by consumers, up to 40% and 70% of salt has been removed from bread and processed meats (9).

Salt in the United Kingdom

The United Kingdom has actively been reducing salt in their food since 2003. Voluntary salt reduction in food manufacturing, public awareness campaigns and mandatory labelling of high salt foods has resulted in a 15% reduction in salt intake since the work started (10).

Salt in Australia and New Zealand

The Healthy Food Partnership, comprising of the Australian Government, public health groups and the food industry is also working towards reducing salt by reformulating food. Voluntary targets were set in 2009 for 10 food categories. However, a 2017 study (11) found only 17 of 33 large Australian food manufacturers have publicly available strategies to reduce salt content in their foods. The authors conclude insufficient efforts were being made to make “significant and comprehensive positive (nutrition) changes” in relation to salt or healthier food products”.

New Zealand has no government-led salt reduction strategy. The New Zealand Heart Foundation (NZHF) has led the charge, urging voluntary reductions from manufacturers through the NZHF ‘Tick’, initiated in 1991. This front-of-pack nutrition logo helps consumers determine heart-healthy foods and encourages ‘Tick’ food manufacturers to produce heart-healthy products. Over a 12 month period (1998/1999) The Tick program resulted in 33 tonnes of salt being removed from food products (12).

In 2010, 50% of New Zealand and 72% of Australian bread had reduced sodium levels to below 450mg/100g or 1.1 g salt per 100 g of bread (13)). Another New Zealand study demonstrated a 12% reduction in salt content in 182 foods over the 10 years to 2013 (14). The graph below shows different food groups and changes in salt quantity from this study.

Salt has been removed from many processed foods but some food groups have increased their salt levels

Even though Australia and New Zealand have voluntary salt reduction programmes (and have seen some results in the food chain) they have not yet reported reductions in population salt intake and it is considered that the WHO global target will not be met in 2025 (15). This is not the case everywhere, 12 countries have reported reduced salt intakes in their population – will this correspond to reduced blood pressures?

New Zealand has a strong and committed non-government organisation, New Zealand Heart Foundation, to lead the salt reduction initiatives using food reformulation, front-of-pack labelling and consumer education but is this enough? Do we need a government led salt reduction programme to provide more resources and maybe even legislate?